rweng/jquery-datatables-rails — pull request #20 by Genkilabs (2012-07-03 17:53:07+00:00)
Title: Update dataTables to 1.9.2 and fixedColumns to 2.0.4dev

Updated the Javascript files. This should resolve this fixedColumns sorting issue:
http://datatables.net/forums/discussion/9596/fixedcolumns-and-sorting-problem#Item_4

Just copied those two files from the repo, no other changes.
It works on my own project but I did not test beyond that.